Laryngeal tube use in out-of-hospital cardiac arrest by paramedics in Norway

Procedural Sedation Intubation in a Paramedic-Staffed Helicopter Emergency Medical System in Northern Finland

OBJECTIVE

Airway management to ensure sufficient gas exchange is of major importance in emergency care. Prehospital endotracheal intubation (ETI) by paramedics is a widely debated method to ensure a patent airway. ETI is performed with procedural sedation in comatose patients because of the regulation. The use of medications increases the rate of successful airway management compared with nonmedication ETI and may also improve outcomes in patients with traumatic brain injury. In the absence of an operative emergency physician and with long distances, paramedic-induced airway management may increase the survival of patients in selected scenarios. A paramedic-staffed helicopter emergency medical system in Northern Finland operates in a rural area without an emergency physician and paralytic medications and treats critically ill patients using basic or advanced life support ground units. The aim of this study was to evaluate the success rates of ETI performed by a small, appropriately trained, and experienced group of 8 nurse paramedics in an out-of-hospital setting.

METHODS

The inclusion criterion for the study was an attempted intubation in patients with medical or traumatic indication for airway management by nurse paramedic.

RESULTS

Fifty-one patients were treated with ETI. The first-pass success rate was 72.5%, the second-pass success rate was 94.1%, and the overall success rate was 100% within 4 attempts. The median on-scene time was 54 minutes, and there were no signs of aspiration during laryngoscopy or after successful ETI. The primary mortality rate was 11.7%.

CONCLUSION

The use of a rigid standard operating procedure for paramedic rapid sequence induction, paralytics, a video laryngoscope, and a gum elastic bougie might positively affect the ETI first-pass success rate. A follow-up study after these future modifications is needed. This small study suggests that intubation might be 1 option for airway management by an experienced nonanesthesiologist in Lapland.

Comparative Analysis of the Effectiveness of Performing Advanced Resuscitation Procedures Undertaken by Two- and Three- Person Basic Medical Rescue Teams in Adults under Simulated Conditions

(1) Objective: Paramedics as a profession are a pillar of the State Medical Rescue system. The basic difference between a specialist and a basic team is the composition of members. The aim of the study was to benchmark the effectiveness of performing advanced resuscitation procedures undertaken by two- and three-person basic emergency medical teams in adults under simulated conditions. (2) Design: The research was observational. 200 two- and three-people basic emergency medical teams were analyzed during advanced resuscitation procedures, ALS (Advanced Life Support) in adults under simulated conditions. (3) Method: The study was carried out among professionally active and certified paramedics. It lasted over two years. The study took place under simulated conditions using prepared scenarios. (4) Results: In total, 463 people took part in the study. The analysis of the survey results indicates that the efficiency of three-person teams is superior to the activities performed by two-person teams. Three-person teams were quicker to perform rescue actions than two-person teams. The two-person teams were much quicker to assess the condition of victims than the three-person teams. The three-person teams were more likely to check an open airway. The three-person teams were more efficient in assessing the heart rhythm and current condition of victims. It was demonstrated that three-person teams were more effective during electrotherapy. The analysis demonstrated that three-person teams were significantly faster and more efficient in chest compressions. Three-person teams were less likely to use emergency airway techniques than two-person teams. The results indicate that three-person teams administered the first dose of adrenaline significantly faster than two-person teams. For the “call for help”, the three-person teams were found to be more effective. (5) Conclusion: Paramedics in three-person teams work more effectively, make a proper assessment of heart rhythm and monitor when taking advanced actions. The quality of ventilation and BLS in both groups studied is insufficient. Numerous errors have been observed in two-person teams during pharmacotherapy.

EMT-led laryngeal tube vs. face-mask ventilation during cardiopulmonary resuscitation - a multicenter prospective randomized trial

Background

Laryngeal tube (LT) application by rescue personnel as an alternate airway during the early stages of out-of-hospital cardiac arrest (OHCA) is still subject of debate. We evaluated ease of handling and efficacy of ventilation administered by emergency medical technicians (EMTs) using LT and bag-valve-mask (BVM) during cardiopulmonary resuscitation of patients with OHCA.

Methods

An open prospective randomized multicenter study was conducted at six emergency medical services centers over 18 months. Patients in OHCA initially resuscitated by EMTs were enrolled. Ease of handling (LT insertion, tight seal) and efficacy of ventilation (chest rises visibly, no air leak) with LT and BVM were subjectively assessed by EMTs during pre-study training and by the attending emergency physician on the scene. Outcome and frequency of complications were compared.

Results

Of 97 eligible patients, 78 were enrolled. During pre-study training EMTs rated efficacy of ventilation with LT higher than with BVM (66.7% vs. 36.2%, p = 0.022), but efficacy of on-site ventilation did not differ between the two groups (71.4% vs. 58.5%, p = 0.686). Frequency of complications (11.4% vs. 19.5%, p = 0.961) did not differ between the two groups.

Conclusions

EMTs preferred LT ventilation to BVM ventilation during pre-study training, but on-site there was no difference with regard to efficacy, ventilation safety, or outcome. The results indicate that LT ventilation by EMTs during OHCA is not superior to BVM and cannot substitute for BVM training. We assume that the main benefit of the LT is the provision of an alternative airway when BVM ventilation fails. Training in BVM ventilation remains paramount in EMT apprenticeship and cannot be substituted by LT ventilation.

Trial registration

ClinicalTrials.gov (NCT01718795).

Electronic supplementary material

The online version of this article (10.1186/s13049-017-0446-1) contains supplementary material, which is available to authorized users.

Unrecognized failed airway management using a supraglottic airway device

BACKGROUND

911 Emergency Medical Services (EMS) systems utilize supraglottic devices for either primary advanced airway management, or for airway rescue following failed attempts at direct laryngoscopy endotracheal intubation. There is, however, limited data on objective confirmation of supraglottic airway placement in the prehospital environment. Furthermore, the ability of EMS field providers to recognize a misplaced airway is unknown.

METHODS

Retrospective review of patients who underwent airway management using the King LTS-D supraglottic airway in a large urban EMS system, between 3/1/15-9/30/2015. Subjective success was defined as documentation of successful airway placement by the EMS provider. Objective success was confirmed by review of waveform capnography, with the presence of a 4-phase waveform greater than 5mmHg. Sensitivity and specificity of the field provider's assessment of success were then calculated.

RESULTS

A total of 344 supraglottic airway attempts were reviewed. No patients met obvious death criteria. 269 attempts (85.1%) met criteria for both subjective and objective success. 19 attempts (5.6%) were recognized failures by the EMS provider. 47 (13.8%) airways were misplaced but unrecognized by the EMS provider. 4 attempts (1.2%) were correctly placed but misidentified as failures, leading to the unnecessary removal and replacement of the airway. Sensitivity of the provider's assessment was 98.5%; specificity was 28.7%.

CONCLUSION

The use of supraglottic airway devices results in unrecognized failed placement. Appropriate utilization and review of waveform capnography may remedy a potential blind-spot in patient safety, and systemic monitoring/feedback processes may therefore be used to prevent unrecognized misplaced airways.

Laryngeal tube suction for airway management during in-hospital emergencies

OBJECTIVE:

The role of supraglottic airway devices in emergency airway management is highlighted in international airway management guidelines. We evaluated the application of the new generation laryngeal tube suction (LTS-II/LTS-D) in the management of in-hospital unexpected difficult airway and cardiopulmonary resuscitation.

METHODS:

During a seven-year period, patients treated with a laryngeal tube who received routine anesthesia and had an unexpected difficult airway (Cormack Lehane Grade 3-4), who underwent cardiopulmonary resuscitation, or who underwent cardiopulmonary resuscitation outside the operating room and had a difficult airway were evaluated. Successful placement of the LTS II/LTS-D, sufficient ventilation, time to placement, number of placement attempts, stomach content, peripheral oxygen saturation/end-tidal carbon dioxide development (SpO2/etCO2) over 5 minutes, subjective overall assessment and complications were recorded.

RESULTS:

In total, 106 adult patients were treated using an LTS-II/LTS-D. The main indication for placement was a difficult airway (75%, n=80), followed by cardiopulmonary resuscitation (25%, n=26) or an overlap between both (18%, n=19). In 94% of patients (n=100), users placed the laryngeal tube during the first attempt. In 93% of patients (n=98), the tube was placed within 30 seconds. A significant increase in SpO2 from 97% (0-100) to 99% (5-100) was observed in the whole population and in cardiopulmonary resuscitation patients. The average initial etCO2 of 39.5 mmHg (0-100 mmHg) decreased significantly to an average of 38.4 mmHg (10-62 mmHg) after 5 minutes. A comparison of cardiopulmonary resuscitation patients with non-cardiopulmonary resuscitation patients regarding gastric contents showed no significant difference.

CONCLUSIONS:

LTS-D/LTS-II use for in-hospital unexpected difficult airway management provides a secure method for primary airway management until other options such as video laryngoscopy or fiber optic intubation become available.

Insertion Success of the Laryngeal Tube in Emergency Airway Management

Background. Emergency airway management (AM) is a priority when resuscitating critically ill or severely injured patients. The goal of this study was to determine the success rates of LT insertion during AM. Methods. Studies that included LT first-pass insertion (FPI) and overall-pass insertion (OPI) success by emergency medical services and in-hospital providers performing AM for emergency situations as well as for scheduled surgery published until July 2014 were searched systematically in Medline. Results. Data of 36 studies (n = 1,897) reported a LT FPI success by physicians of 82.5% with an OPI success of 93.6% (p < 0.001). A cumulative analysis of all 53 studies (n = 3,600) led to FPI and OPI success of 80.1% and 92.6% (p < 0.001), respectively. The results of 26 studies (n = 2,159) comparing the LT with the laryngeal mask airway (LMA) demonstrated a FPI success of 77.0 versus 78.7% (p = 0.36) and an OPI success of 92.2 versus 97.7% (p < 0.001). Conclusion. LT insertion failed in the first attempt in one out of five patients, with an overall failure rate in one out of 14 patients. When compared with the LT, the LMA had a cumulative 5.5% better OPI success rate.

Airway management in out-of-hospital cardiac arrest in Finland: current practices and outcomes

Background

Though airway management methods during out-of-hospital cardiac arrest (OHCA) remain controversial, no studies on the topic from Finland have examined adherence to OHCA recommendations in real life. In response, the aim of this study was to document the interventions, success rates, and adverse events in airway management processes in OHCA, as well as to analyse survival at hospital discharge and at follow-up a year later.

Methods

During a 6-month study period in 2010, data regarding all patients with OHCA and attempted resuscitation in southern and eastern Finland were prospectively collected. Emergency medical services (EMS) documented the airway techniques used and all adverse events related to the process. Study endpoints included the frequency of different techniques used, their success rates, methods used to verify the correct placement of the endotracheal tube, overall adverse events, and survival at hospital discharge and at follow-up a year later.

Results

A total of 614 patients were included in the study. The incidence of EMS-attempted resuscitation was determined to be 51/100,000 inhabitants per year. The final airway technique was endotracheal intubation (ETI) in 413 patients (67.3 %) and supraglottic airway device (SAD) in 188 patients (30.2 %). The overall success rate of ETI was 92.5 %, whereas that of SAD was 85.0 %. Adverse events were reported in 167 of the patients (27.2 %). Having a prehospital EMS physician on the scene (p < .001, OR 5.05, 95 % CI 2.94–8.68), having a primary shockable rhythm (p < .001, OR 5.23, 95 % CI 3.05–8.98), and being male (p = .049, OR 1.80, 95 % CI 1.00–3.22) were predictors for survival at hospital discharge.

Conclusions

This study showed acceptable ETI and SAD success rates among Finnish patients with OHCA. Adverse events related to airway management were observed in more than 25 % of patients, and overall survival was 17.8 % at hospital discharge and 14.0 % after 1 year.

[The supraglottic airway in the prehospital setting]

The supraglottic airway (SGA) is increasingly considered as a more effective alternative for emergency ventilation compared to bag mask ventilation and is propagated as an "easily" manageable method, compared to endotracheal intubation especially under the often adverse out-of-hospital conditions. Since the skill can easily be acquired during mannequin training, more and more rescue services train their personnel in the use of SGA devices and allow or even recommend their application also by nonphysicians. This recommendation, however, is not unequivocally supported by properly designed and conducted trials. Moreover, the solely available observational studies show contradictory results. Neither superiority nor inferiority of SGAs has been shown. They may, however, be accepted as an addendum to other prehospital ventilation approaches. The SGA airway comprises various problems and inherited risks similar to other ventilation techniques. Randomized studies investigating different techniques for prehospital emergency ventilation are lacking, as are controlled studies comparing SGA devices.

Impact of laryngeal tube use on chest compression fraction during out-of-hospital cardiac arrest. A prospective alternate month study

AIM

Supraglottic devices are thought to allow efficient ventilation and continuous chest compressions during cardiac arrest. Therefore, the use of supraglottic devices could increase the chest compression fraction (CCF), a critical determinant of patient survival. The aim of this study was to assess the CCF in out-of-hospital cardiac arrest (OHCA) patients ventilated with a supraglottic device.

METHODS

We conducted an open prospective multicenter study with temporal clusters. OHCA patients treated by emergency nurses received either intermittent chest compressions with bag-valve mask ventilations (30:2 rhythm; BVM group); or continuous chest compressions with asynchronous ventilations by laryngeal tube (LT group). The primary endpoint was the CCF assessed using an accelerometer connected to the defibrillator. We also investigated the ease of use of the laryngeal tube.

RESULTS

Eighty-two patients were included (41 in each group); 68% were male and the median age was 68 (54-80) years. Patients and cardiac arrest characteristics did not differ between groups. The CCF was 75% (68-79%) in the LT group and 59% (51-68%) in the BVM group (p<0.01). LT insertion failed in nine out of 40 cases (23%). The median time of LT insertion was 26s (11-56 s). CCF was significantly lower when LT insertion failed (58% (48-74%) vs. 76% (72-80%) when LT insertion succeeded; p=0.01).

CONCLUSION

The use of the LT during OHCA increases the CCF when compared to standard BVM ventilation. However, the impact of LT use on mortality remains unclear.

The novel intubating laryngeal tube (iLTS-D) is comparable to the intubating laryngeal mask (Fastrach) - a prospective randomised manikin study

Background

Supraglottic devices are helpful for inexperienced providers who perform ventilation in emergency situations. Most supraglottic devices do not allow secondary tracheal intubation through the device. The novel intubating laryngeal tube (iLTS-D®) and the intubating laryngeal mask (Fastrach™) are devices that offer supraglottic ventilation and secondary tracheal intubation.

Methods

We evaluated the novel iLTS-D and compared it to the established Fastrach using a manikin-based study. Participants used both devices in a randomised order. The participants conducted four consecutive trials on a manikin. One trial was composed of the following procedures. First, participants ventilated the manikin using either iLTS-D or Fastrach. ‘Time to ventilation’, success rates and number of attempts were recorded for the supraglottic device. Second, participants intubated the manikin through the previously inserted supraglottic device. ‘Time to tracheal ventilation’, success rate and tube localisation were recorded. The primary endpoint was the results of the final fourth trial, which mirrored the standardised training of trials 1, 2 and 3.

Results

A total of 64 participants were enrolled. All of the participants successfully inserted both devices on their first attempt in trial 4. Fastrach was applied 1 s faster in trial 4 than the iLTS-D (median ‘time to ventilation’ Fastrach: 13.5 s., iLTS-D: 14.5 s., p = 0.04). All participants successfully intubated through both devices in trial 4. There was no difference in ‘time to tracheal ventilation’ by tracheal intubation between either device (median ‘time to tracheal ventilation’: Fastrach: 14.0 s., iLTS-D: 14.0 s., p = 0.16).

Conclusion

The iLTS-D performed similarly to the ILMA in insertion and intubation times in a manikin setting.

Feasibility of LMA Supreme for airway management in unconscious patients by ALS paramedics

Background

Airway management to ensure sufficient gas exchange is of major importance in emergency care. The accepted basic technique is to maintain an open airway and perform artificial ventilation in emergency situations is bag-valve mask (BVM) ventilation with manual airway management without airway adjuncts or with an oropharyngeal tube (OPA) only. Endotracheal intubation (ETI) is often referred to as the golden standard of airway management, but is associated with low success rates and significant insertion-related complications when performed by non-anaesthetists. Supraglottic devices (SADs) are one alternative to ETI in these situations, but there is limited evidence regarding the use of SAD in non-cardiac arrest situations. LMA Supreme (LMA-S) is a new SAD which theoretically has an advantage concerning the risk of aspiration due to an oesophageal inlet gastric tube port.

Methods

Forty paramedics were recruited to participate in the study. Adult (>18 years) patients, unconscious due to medical or traumatic cause with a GCS score corresponding to 3–5 and needed airway management were included in the study. Our aim was to study the feasibility of LMA-S as a primary airway method in unconscious patients by advanced life support (ALS) trained paramedics in prehospital care.

Results

Three regional Emergency Medical Service (EMS) services participated and 21 patients were treated during the survey. The LMA-S was placed correctly on the first attempt in all instances 21/21 (100%), with a median time to first ventilation of 9.8 s. Paramedics evaluated the insertion to be easy in every case 21/21 (100%). Because of air leak later in the patient care, the LMA-S was exchanged to an LT-D in two cases and to ETI in three cases (23.81%) by the paramedics. Regurgitation occurred after insertion two times out of 21 (9.52%) and in one of these cases (4.76%), paramedics reported regurgitation inside the LMA-S.

Conclusion

We conclude that the LMA-S seems to be relatively easy and quick to insert in unconscious patients by paramedics. However, we found out that there were ventilation related problems with the LMA-S. Further studies are warranted.

Complications associated with the prehospital use of laryngeal tubes--a systematic analysis of risk factors and strategies for prevention

OBJECTIVE

With the increasing spread of laryngeal tubes (LT) in emergency medicine, complications and side-effects are observed. We sought to identify complications associated with the use of LTs in emergency medicine, and to develop strategies to prevent these incidents.

METHODS

In a prospective clinical study, all patients who had their airways managed in the field with a LT and who were admitted through the emergency department of the Frankfurt University Hospital during a 6 year period were evaluated using anonymised data collection sheets. A team of experts was available 24/7 and was requested whenever a patient was admitted with a LT in place. This team evaluated the condition of the patients with respect to prehospital airway management and was responsible for further advanced airway management. All complications were analysed, and strategies for prevention developed.

RESULTS

One hundred eighty nine patients were included and analysed. The initial cuff pressure of the LTs was 10 0 cm H₂O on the median. Complications consisted of significant tongue swelling (n=73; 38.6%), resulting in life-threatening cannot ventilate, cannot intubate scenarios in two patients (1.0%) and the need for surgical tracheostomy in another patient, massive distension of the stomach (n=20, 10.6%) with ventilation difficulties when LTs without gastric drainage were used; malposition of the LT in the piriform sinus (n=1, 0.5%) and significant bleeding from soft tissue injuries (n=4, 2.1%).

CONCLUSIONS

The prehospital use of LTs may result in severe and even life-threatening complications. Likely, such complications could have been prevented by using gastric drainage and cuff pressure adjustment. Both, prehospital health care providers and emergency department staff should develop a greater awareness of such complications to best avoid them in the future.

Oxygenation, ventilation, and airway management in out-of-hospital cardiac arrest: a review

Recently published evidence has challenged some protocols related to oxygenation, ventilation, and airway management for out-of-hospital cardiac arrest. Interrupting chest compressions to attempt airway intervention in the early stages of OHCA in adults may worsen patient outcomes. The change of BLS algorithms from ABC to CAB was recommended by the AHA in 2010. Passive insufflation of oxygen into a patent airway may provide oxygenation in the early stages of cardiac arrest. Various alternatives to tracheal intubation or bag-mask ventilation have been trialled for prehospital airway management. Simple methods of airway management are associated with similar outcomes as tracheal intubation in patients with OHCA. The insertion of a laryngeal mask airway is probably associated with worse neurologically intact survival rates in comparison with other methods of airway management. Hyperoxemia following OHCA may have a deleterious effect on the neurological recovery of patients. Extracorporeal oxygenation techniques have been utilized by specialized centers, though their use in OHCA remains controversial. Chest hyperinflation and positive airway pressure may have a negative impact on hemodynamics during resuscitation and should be avoided. Dyscarbia in the postresuscitation period is relatively common, mainly in association with therapeutic hypothermia, and may worsen neurological outcome.

Advances in prehospital airway management

Prehospital airway management is a key component of emergency responders and remains an important task of Emergency Medical Service (EMS) systems worldwide. The most advanced airway management techniques involving placement of oropharyngeal airways such as the Laryngeal Mask Airway or endotracheal tube. Endotracheal tube placement success is a common measure of out-of-hospital airway management quality. Regional variation in regard to training, education, and procedural exposure may be the major contributor to the findings in success and patient outcome. In studies demonstrating poor outcomes related to prehospital-attempted endotracheal intubation (ETI), both training and skill level of the provider are usually often low. Research supports a relationship between the number of intubation experiences and ETI success. National standards for certification of emergency medicine provider are in general too low to guarantee good success rate in emergency airway management by paramedics and physicians. Some paramedic training programs require more intense airway training above the national standard and some EMS systems in Europe staff their system with anesthesia providers instead. ETI remains the cornerstone of definitive prehospital airway management, However, ETI is not without risk and outcomes data remains controversial. Many systems may benefit from more input and guidance by the anesthesia department, which have higher volumes of airway management procedures and extensive training and experience not just with training of airway management but also with different airway management techniques and adjuncts.

Evaluation of airway management associated hands-off time during cardiopulmonary resuscitation: a randomised manikin follow-up study

INTRODUCTION

Airway management is an important component of cardiopulmonary resuscitation (CPR). Recent guidelines recommend keeping any interruptions of chest compressions as short as possible and not lasting more than 10 seconds. Endotracheal intubation seems to be the ideal method for establishing a secure airway by experienced providers, but emergency medical technicians (EMT) often lack training and practice. For the EMTs supraglottic devices might serve as alternatives.

METHODS

40 EMTs were trained in a 1-hour standardised audio-visual lesson to handle six different airway devices including endotracheal intubation, Combitube, EasyTube, I-Gel, Laryngeal Mask Airway and Laryngeal tube. EMTs performances were evaluated immediately after a brief practical demonstration, as well as after 1 and 3 months without any practice in between, in a randomised order. Hands-off time was pair-wise compared between airway devices using a repeated-measures mixed-effects model.

RESULTS

Overall mean hands-off time was significantly (p<0.01) lower for Laryngeal tube (6.1s; confidence interval 5.2-6.9s), Combitube (7.9s; 95% CI 6.9-9.0s), EasyTube (8.8s; CI 7.3-10.3s), LMA (10.2s; CI 8.6-11.7s), and I-Gel (11.9s; CI 10.2-13.7s) compared to endotracheal intubation (39.4s; CI 34.0-44.9s). Hands-off time was within the recommended limit of 10s for Combitube, EasyTube and Laryngeal tube after 1 month and for all supraglottic devices after 3 months without any training, but far beyond recommended limits in all three evaluations for endotracheal intubation.

CONCLUSION

Using supraglottic airway devices, EMTs achieved a hands-off time within the recommended time limit of 10s, even after three months without any training or practice. Supraglottic airway devices are recommended tools for EMTs with lack of experience in advanced airway management.